BRAINCAKEThe Founder Effect
The founder effect happens when a small group of individuals leaves a large population and starts a new population somewhere else, for example by colonising an island.
The founders carry only a small, random sample of the alleles in the original gene pool. By chance, the allele frequencies in this group are likely to be different from those in the parent population. Some alleles may be missing altogether, and a rare allele may be much more common in the founders than it was originally.
The new population grows from these founders, so its gene pool reflects their alleles, not those of the original population. If the new population stays isolated, these differences persist, and it has lower genetic diversity than the parent population.
Sign in free to see the rest of this lesson, the R.E.C.I.P.E. recall steps and the quiz
BrainCake is free. Make an account in seconds and pick up where this page stops.
Key terms in this lesson
- genetic diversity
- The range of different alleles present in the gene pool of a population.
More in Gene Pools
- Different Sized Populations
- Isolation
- Selection Pressure
- Population Bottlenecks
- Stabilising Selection
- Directional Selection
- Disruptive Selection
- Genetic Drift
All 16 lessons in Gene Pools · All Edexcel A-level Biology topics